Secrets that you keep
by Adolphaxxx
Summary: Another run in with Moriaty leads to Sherlock and Sally being kidnapped. But what is Sally hiding? And will Sherlock work it out in time?
1. Chapter 1

Chapter 1

**Hey guys! I can't sleep tonight, so I thought I'd finish off this fic for you. It's a 3 parter, and I'm uploading them all now. Oh, there is a little bit of swearing in this, but it's just one word, so I didn't see the point in a higher rating.I apologise if there are some parts which are less than coherent, but it is now 4 in the morning, and I haven't slept at all. So here we go, I hope you enjoy it! XD **

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Sherlocks feet pounded against the ground as he chased after the perpetrator of the latest in a long line of gruesome me murders. The man in question was Simon White, 34 years old, with an ex wife and two children, his first three victims. It had taken Sherlock just 5 minutes at the scene of the last murder to link the crimes to Simon, and he had tracked the man down almost immediately. The only catch was that Lestrade had insisted Donovan accompanied him. A small smirk accompanied thoughts of Sally. Sherlock had left her two blocks behind as be ran, and she wasn't happy about it.

Rushing round the corner, Sherlock realised the suspect had managed to run into a dead end. Sherlock walked slowly towards the man, putting his hand in one of his coat pockets and pulling out a set of handcuffs he'd stolen from Lestrade a few months ago, after John confiscated his. A voice from behind stopped him in his tracks.

"Sherlock! Sherlock darling, did you miss me?"

Moriaty._ Of course._ Sherlock turned, thoughts of the murderer behind him all but forgotten.

"So I take it this is another of your games. Really, you could have picked something more interesting than just serial murders."

"Oh Sherlock, you can insult me all you like later, but for now, we need to get going." Sherlock looked, confused, at the consulting criminal, but staggered and fell as he felt a needle being pushed into his neck. He reached up to try and push off his attacker, but his knees buckled and he fell to the ground.

"Oh, and Sherlock, don't worry about your little police friend, we picked her up a few minutes ago." Sherlock looked up to see a sick smile on the face he hated so much.

As Sally rolled over, a searing pain shot through her side, and when she tried to open her eyes, the pounding in her head intensified to the point where she cried out. After taking a few deep breaths she tried again. This time, she managed to fully open her eyes and began to take in her surroundings. Beginning with the man sat opposite her. Her brain was still fuzzy from whatever the hell it was they used to knock her out. She recognised him, she knew that long coat, the messy hair, the cheekbones, and the vacant expression. But she couldn't remember who he was. He turned to look at her, and, noticing she was awake, got up and walked towards her. She tried to sit up, but the pain flared again in her side and chest.

"Ah Sally, you're awake. It took you long enough."

"Freak, of course, it's you." _How on Earth did she not recognise him?_ She made another attempt to sit up, and this time managed it, ignoring the burning she coursing through her body.

"Of course it's me, Sally. Anyway, now you're awake, we can get out of here." Sherlock walked away from her and towards the door. Bracing herself, she used the wall to pull herself to her feet. It hurt like hell, but if the freak was up and about, she wasn't going to seem weak by sitting waiting for him to do all the hard work.

_What was wrong with Sally?_ Sherlock was working on the door lock, but it was proving impossible. And whilst he was working, he was thinking. There was something wrong with Donovan, he just didn't know what. She was very pale, and she was shaking badly. Her injures weren't too bad, she'd have a lot of bruises, but no broken bones. So what was wrong? It was driving him a little but crazy.

Sally had been stood watching the detective for about 10 minutes. He still hadn't got the door open. But, thankfully, her ribs felt a bit better. At least each breath no longer sent pain shooting round her body. Now, however, she had bigger problems to contend with. She was dizzy already, not a good sign.

"Sherlock, how long were we out for?" Sherlock looked thoughtful for a second before he replied.

"Well, by my reckoning, it must be two and a half hours after we were captured." _Shit_. That made it over four hours since she last took any medication. Not good.

Half an hour later, and Sherlock had given up with the lock and had chosen to pace across the room. It had been nearly an hour since he woke up, and still no sign of Moriaty. He paced back and forth, considering the situation. He knew John and Lestrade would find them eventually, but he would rather not rely on them and get himself out of trouble. A thud from across the room pulled him out if his thoughts. He looked towards the source if the noise, finding Donovan slumped in a heap on the floor. He walked over and knelt down next to her. Her breathing was very laboured, she was as white as a ghost, and she was shaking a lot more than before. He reached out and grabbed hold of her wrist.

"Oi, freak, let go." She sounded exhausted, and her attempts to remove his hand were proving useless. Her pulse was racing though, and she had a definite temperature.

"What's the matter Donovan? And don't try telling me that you're fine, because you're obviously not. Also, this obviously isn't from an injury you've gained today. So tell me, what's wrong?"

God, Sherlock was infuriating. Why couldn't he just leave her alone. Lestrade would get there soon enough, and she'd be okay. And there wasn't anything the freak could do, so why did he need to know. Anyway, if he was so clever, how come he hadn't worked it out yet? A wry smile formed on her lips at the thought. She could hear him talking to her, but she couldn't make sense of the words. She was so tired, all she wanted to do was sleep.

"No, Sally, don't go to sleep. I need you to stay awake for me. Open your eyes." It was no use, she wanted to go to sleep, and there was nothing the freak could do to stop her. She could feel herself slowly slipping into the dark abyss of sleep.

Whatever was wrong with her, if she passed out now, Sherlock doubted he'd get her back. He had to think of something, and quickly. Something to annoy her. An idea emerged in his head.

"If you go to sleep, I'll tell Anderson you've been cheating on him." Sally's eyes shot open.

"You wouldn't dare." Well, that worked better than he hoped.

"You know me well enough to know that I would. In a heart beat. So either stay awake and answer my questions, or I'll tell him." Finally, he could find out what was wrong with her.

"What do you want to know?"

"That's better. Now, what's the matter with you?"

"Why do you care?" Well, at least she had the sense not to deny it any more.

"We've been kidnapped by a psychopath, and are now being held someplace underground and way out of the city. Whilst I am certain John and Greg will find us eventually, you don't look like you can wait very long. If you tell me what's wrong with you, I may be able to help."

"Underground? Where did that come form? And once again, why would you care? We spend most of our time making each other's lives as difficult as we can."

"I'm not completely devoid of all feelings, you know. Just because I dislike you it doesn't mean I want to see you dead. Also, sharing a cell with a corpse would be incredibly boring, I'd have no one to talk to. And I wouldn't be able to do any experiments, because I've not got any equipment."


	2. Chapter 2

Chapter 2

_What was wrong with Sally?_ Sherlock was pacing up and down in the cell trying to think. No matter how many questions he asked, she wouldn't answer.

"Sherlock, if you don't stop pacing, I swear I'm going to kill you." Sherlock smirked, knowing that whilst she would probably love to, she didn't have the energy. "I think we both know that's never going to happen Sally. You don't even have the energy to stand up, so how are you planning on killing me?" He smirked again as he could feel Sally's glare aimed at the back if his head. The smile was wiped off his face, however, as he turned to look at her. She was paler than the last time he had looked, and now she was sweating and shaking too. He walked over to her and crouched down next to her again.

"Sally, you're going to have to tell me what's wrong. I might be able to help you."

Sally knew things were getting bad now. But she still didn't want the freak to know. She didn't fancy her chances, however, if she got to the point where her body started to shut down and she fell into a coma. Would the freak know what to do? Probably, but he was just as likely to use her as an experiment. She sighed and decided that she'd have to tell him. "Alright freak, since you're so interested, I'll tell you."

"Just telling me is boring. We've still got time to kill before John and Lestrade get here, so let me try and guess." Unbelievable. Absolutely unbelievable. He had spent all this time trying to pry it out of her, but as soon as she decides to tell him, he doesn't want her help anymore, he'll guess it on his own. Well good luck with that.

"Right, well, let's start with the obvious. Sweating, shaking, pallor, dilated pupils. Could be drug related, but I don't think you're stupid enough for that. From the way you keep rubbing your temples, I assume you've got a headache, yes? What else. Clumsiness, ataxia, fatigue. What else, what else?" Sherlock paused his ramblings to watch as Sally stretched and rubbed her hands, not as though she was trying to warm them, but as though she was trying to rid herself of pins and needles. "Hmm, paresthesia of the extremities. Oh!" He suddenly exclaimed. Sally jumped in surprise. "Hypoglycaemia!"

_Oh great, the freak had worked it out._ Sally just looked at him and raised her eyebrows, she didn't have the energy to say anything to him. He stared back at her. "You're used to this, so obviously this isn't the first time. So given that fact, it's not just that you haven't eaten in a while. You aren't incredibly skinny, so it's unlikely to be the result of a long term eating disorder." Sally raised her eyebrows at him again, this time in an incredulous way. She want expecting that to come out of his mouth. "You're not an alcoholic, so it isn't that." Sherlock paused for a moment, before a smile lit up his features. "You're diabetic." Sally just stared at him. Yes he was right, but he didn't have to look so happy about it, did he.

Sherlock kept on smiling to himself. He was pleased with how fast he had managed to work out what was wrong with her._ Just over 30 seconds_. The smile soon fell off his face, however, when be realised the implications of this. "Ah, yes, I can see why that might be a problem, given the situation. You don't happen to have any food on you, do you?" A single raised eyebrow from Sally was an answer enough. "No, because that would just be ridiculous. No, Sally, don't go to sleep."

Sally had got fed up of the freaks ramblings. She just wanted to sleep. "No Sally, stay awake. I meant what I said before, you know. Sally. Sally!" The freaks voice finally faded to silence, and Sally drifted into a deep slumber.


	3. Chapter 3

Chapter 3

**So here we are, the end. I hope you've liked it. XD Apologies for the fact the chapters kept getting shorter. That was completely unintentional, but it just sorta happened. Well anyway, here you are. **

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_Beep...beep...beep.._.

Sally awoke to the constant beeping if a heart monitor. She opened her eyes and found herself staring at a white tiled ceiling.

"You're awake then?" Well that she wasn't expecting. She turned her head and found Sherlock sat in the chair next to her bed.

"No offence freak, but what are you doing here?" Okay, that sounded less insulting in her head.

"I thought you might like some company, but if you'd rather I left..." Sherlock started to get up out of the chair.

"Sit back down, for gods sake. What the hell happened? How did I end up in here?"

"Well I was right in saying that John and Lestrade would find us. They got there about 10 minutes after you passed out. It took the idiots another 5 minutes to open the door. Lestrade had already phoned an ambulance, and they brought you here. You really were being stupid, going out without any medication. You could have died."

"I didn't know you cared."

"Oh, I don't, but Lestrade would get very suspicious if you'd been sent to work with me then all of a sudden you dropped dead." The two stared at each other for a minute before Sherlock got up and walked towards the door. Sally sighed and closed her eyes. Realising she'd not heard the door open, she opened her eyes again and looked over to the door. Sherlock was still stood there.

"I've decided that, given the circumstances, it would be pointless for me to tell Anderson you've been sleeping around. I mean, it was hardly your fault you fell unconscious." Sally smiled as she remembered Sherlock bargaining with her.

"However, I think you should know, you aren't the only one. He's got a new girlfriend. Get better soon." And with that, Sherlock disappeared through the door. Sally sighed in frustration and slammed her head back against the pillow. T_hanks freak. _


End file.
